Witchcraft beliefs structure social interactions

Nature Human Behaviour

January 9, 2018

Being labelled a witch - or ‘zhu’ - can affect who marries, helps and trades between households in villages in southwest China, reports a paper published in Nature Human Behaviour this week. This behaviour may function to spite potential rivals.

Negative labels that ostracize individuals - such as being named a witch - have a long and widespread history in human societies, but their social function is not well understood. While some research suggests that witchcraft labels are used to mark untrustworthy or uncooperative individuals, others have suggested that they function to undermine competitors. To date, there has been little quantitative data to explore these alternatives.

Ruth Mace, Ting Ji, Yi Tao and colleagues conducted interviews and gift-giving experiments in 800 households across five villages of the rural Mosuo people. Among the Mosuo, female heads of households and their daughters are called zhu when others believe that they have supernatural powers and engage in food poisoning. By visually reconstructing the social interactions among households, the authors found a social network of households clearly divided between zhu and non-zhu. Zhu households were largely excluded from intermarriage and from trading farm labour with non-zhu households; however, zhu households made up for this by preferentially interacting with each other in small sub-networks. Importantly, the authors found that zhu households were no less cooperative than others in economic games, suggesting that ‘zhu’ isn’t being used to mark uncooperative or untrustworthy households.

The authors suggest that witch-labelling may have evolved as a way for people to besmirch rivals and gain a competitive advantage in reproduction and resources.